Method for forming a package structure

Abstract

A method for forming a package structure is provided. The method includes forming a grain structure above a first surface of a first substrate, and forming a plurality of electrical connectors below a second surface of the first substrate. The method also includes forming a first protrusion structure below the second surface of the first substrate, and the electrical connector is surrounded by the first protrusion structure. The method also includes forming a second protrusion structure above a second substrate, and bonding the first substrate to the second substrate. The electrical connector is surrounded by the second protrusion structure, and the first protrusion structure does not overlap with the second protrusion structure.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a packaging structure, and more particularly, to a method for forming a packaging structure. Background Art

[0002] Semiconductor devices are used in a variety of electronic applications, such as personal computers, mobile phones, digital cameras, and other electronic devices. Semiconductor devices are typically manufactured by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductive layers of materials over a semiconductor substrate, and using lithography to pattern the various material layers to form circuit components and elements thereon. Many integrated circuits are typically manufactured on a single semiconductor wafer, and the individual dies on the wafer are singulated by cutting along scribe lines between the integrated circuits. The individual dies are typically packaged separately, such as in a multi-chip module or other type of package.

[0003] New packaging technologies such as package on package (PoP) have been developed, in which a top package with a device die is bonded to a bottom package with another device die. By adopting the new packaging technology, various packages with different or similar functions are integrated together.

[0004] While existing packages and methods of making packages have generally been adequate for their intended purposes, they have not been completely satisfactory in all respects. Summary of the invention

[0005] According to some embodiments of the present disclosure, a method for forming a packaging structure is provided. The method includes forming a grain structure above a first surface of a first substrate, and forming a plurality of electrical connectors below a second surface of the first substrate. The method also includes forming a first protrusion structure below the second surface of the first substrate, and the electrical connector is surrounded by the first protrusion structure. The method also includes forming a second protrusion structure above the second substrate, and bonding the first substrate to the second substrate. The electrical connector is surrounded by the second protrusion structure, and the first protrusion structure does not overlap with the second protrusion structure.

[0006] According to some embodiments of the present disclosure, a method for forming a packaging structure is provided. The method includes forming a grain structure above a first surface of a first substrate, and forming a plurality of electrical connectors below a second surface of the first substrate. The method also includes forming a first protrusion structure next to the electrical connector, and pressurizing a portion of the plurality of electrical connectors in the first area from the second surface of the first substrate so that each of the electrical connectors in the first area has a substantially flat bottom surface. The method also includes forming a second protrusion structure and a third protrusion structure above the second substrate, and the second protrusion structure and the third protrusion structure are of different heights. The method includes bonding the first substrate to the second substrate, and the first protrusion structure is located between the second protrusion structure and the third protrusion structure.

[0007] According to some embodiments of the present disclosure, a method for forming a packaging structure is provided. The method includes forming a grain structure above a first substrate, and forming a plurality of electrical connectors below the first substrate. The method also includes forming a first support structure below the first substrate, and the first support structure has a first height, and the method also includes performing a pressurization process on the electrical connector so that the electrical connector includes a first group of pressurized electrical connectors and a second group of non-pressurized electrical connectors. The method also includes using the electrical connector to join the first substrate to the second substrate, and one of the first group of pressurized electrical connectors has a second height. One of the second group of non-pressurized electrical connectors has a third height. The first height is less than the second height, and the second height is less than the third height. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The following will be described in detail with reference to the accompanying drawings of the specification. It should be noted that, in accordance with standard practice in the industry, various features are not shown in proportion and are only used for illustration. In fact, the size of the elements may be arbitrarily enlarged or reduced to clearly show the features of the present disclosure.

[0009] Figures 1A to 1M Cross-sectional views are shown at various stages of forming a package structure according to some embodiments of the present disclosure.

[0010] Figure 1M' A cross-sectional view of a package structure according to some embodiments of the present disclosure is shown.

[0011] Figure 2A A top view of a ring-shaped structure according to some embodiments of the present disclosure is shown.

[0012] Figure 2B Some embodiments of the present disclosure are shown Figure 1K A top view of the first protruding structure in FIG.

[0013] Figure 2C Some embodiments of the present disclosure are shown Figure 1LA top view of the second protruding structure in FIG.

[0014] Figure 2C' A top view of a second protruding structure and a third protruding structure according to some embodiments of the present disclosure is shown.

[0015] FIG. 3A to FIG. 3E Cross-sectional views are shown at various stages of forming a package structure according to some embodiments of the present disclosure.

[0016] Figure 3E' A cross-sectional view of a package structure according to some embodiments of the present disclosure is shown.

[0017] Figure 4A Some embodiments of the present disclosure are shown Figure 3D A top view of the first protruding structure in FIG.

[0018] Figure 4B Some embodiments of the present disclosure are shown Figure 3E A top view of the second protruding structure in FIG.

[0019] Figure 4B' A top view of a second protruding structure and a third protruding structure according to some embodiments of the present disclosure is shown.

[0020] Figure 5 A cross-sectional view of a package structure according to some embodiments of the present disclosure is shown.

[0021] Figure 6 A cross-sectional view of a package structure according to some embodiments of the present disclosure is shown.

[0022] Figure 7 A cross-sectional view of a package structure according to some embodiments of the present disclosure is shown.

[0023] Figure 8 A cross-sectional view of a package structure according to some embodiments of the present disclosure is shown.

[0024] Description of reference numerals:

[0025] 10: Grain structure

[0026] 11: First Area

[0027] 12: Second Area

[0028] 18: Molding device

[0029] 20: Pressurization process

[0030] 22: Installation

[0031] 100a, 100b, 100c, 100d, 100e, 100g, 100h: Package structure

[0032] 102: Substrate / first substrate

[0033] 102a, 160a, 180a: first surface

[0034] 102b, 160b, 180b: Second surface

[0035] 104: Conductive structure

[0036] 106,124: Conductive layer

[0037] 108: Dielectric layer

[0038] 110,122: Internal connection structure

[0039] 112,126,152,170: Conductive pads

[0040] 120: Semiconductor grains

[0041] 121: Substrate

[0042] 128,154: Conductive connector

[0043] 130: Bottom filling layer

[0044] 140,164: Encapsulation layer

[0045] 142: Carrier substrate

[0046] 150: Passivation layer

[0047] 160: Second substrate

[0048] 166: Ring structure

[0049] 171: Flux

[0050] 172,190,192: Electrical connector

[0051] 174: Conductive materials

[0052] 178: First protruding structure

[0053] 180: The third substrate

[0054] 182: Second protruding structure

[0055] 184: Third prominent structure

[0056] D1: First width

[0057] D2: Second width

[0058] D3: Third width

[0059] G: Distance

[0060] H1: First height

[0061] H1': original height

[0062] H2: Second height

[0063] H3: The third height

[0064] H4: The fourth height

[0065] H5: Fifth height

[0066] L1: first length

[0067] L2: Second length

[0068] L3: The third length

[0069] S1: First Space

[0070] S2: First Space

[0071] W1: First width

[0072] W2: Second width

[0073] W3: Third width DETAILED DESCRIPTION

[0074] The following disclosure provides a variety of different embodiments or examples to implement the different features of the present disclosure. The following describes specific examples of various components and arrangements to simplify the present disclosure. Of course, these are only examples and are not intended to be limiting. For example, if the specification describes that a first feature is formed above or on a second feature, it means that an embodiment in which the first feature and the second feature are in direct contact may be included, and an embodiment in which an additional feature is formed between the first feature and the second feature so that the first feature and the second feature are not in direct contact may be included. In addition, in various examples, the present disclosure may use repeated numbers and / or markings. Such repetition is for the purpose of simplicity and clarity and does not represent the relationship between the various embodiments and / or configurations discussed.

[0075] Some variations of the embodiments are described. Similar reference numerals are used to indicate similar elements throughout the various views and illustrative embodiments. It should be understood that additional operations may be provided before, during, and after the method, and that some of the operations described may be replaced or eliminated for other embodiments of the method.

[0076] Other features and processes may also be included. For example, a test structure may be included to assist in verification testing of a three-dimensional package or three-dimensional integrated circuit (3DIC) device. The test structure may include, for example, a test pad formed in a redistribution layer or on a substrate, which allows testing of the three-dimensional package or three-dimensional integrated circuit, using probes and / or probe cards, etc. Verification testing may be performed on intermediate structures as well as final structures. In addition, the structures and methods disclosed herein may be used in conjunction with a test method for intermediate verification of known good die to increase yield and reduce cost.

[0077] Embodiments for semiconductor device structures and methods of forming the same are provided. Figures 1A to 1M A cross-sectional view of various stages of forming a package structure 100a according to some embodiments of the present disclosure is shown. The package structure may be a chip-on-wafer-on-substrate (CoWoS) package or another suitable package. The package structure includes a grain structure formed on a first substrate, and the first substrate is bonded to a second substrate. In order to prevent warpage of the first substrate, a protruding structure is formed below the first substrate, and another protruding structure is formed above the second substrate. The first protruding structure is configured to provide a mechanism and structural support for the substrate. The first protruding structure and the second protruding structure are between the first substrate and the second substrate.

[0078] refer to Figure 1A , providing a first substrate 102. The first substrate 102 includes a first surface 102a and a second surface 102b. The substrate 102 can be made of silicon or other semiconductor materials. Alternatively or additionally, the substrate 102 can include other elemental semiconductor materials such as germanium. In some embodiments, the substrate 102 is made of a compound semiconductor, such as silicon carbide, gallium arsenide, indium arsenide, or indium phosphide. In some embodiments, the substrate 102 is made of an alloy semiconductor, such as silicon germanium, silicon germanium carbide, gallium arsenide phosphide, or indium gallium phosphide. In some embodiments, the substrate 102 includes an epitaxial layer. For example, the substrate 102 has an epitaxial layer overlying a bulk semiconductor.

[0079] A plurality of conductive structures 104 are formed in the first substrate 102. The conductive structures 104 extend from a first surface 102a of the first substrate 102 toward a second surface 102b of the first substrate 102.

[0080] In some embodiments, the conductive structure 104 is formed by forming a plurality of trenches (not shown) extending from the first surface 102a of the first substrate 102. Then, the conductive structure 104 is formed in each trench. In some embodiments, before forming the conductive structure 104, a barrier layer (not shown) is formed in the trench.

[0081] Afterwards, if Figure 1B As shown, an interconnect structure 110 is formed over the conductive structure 104 and the first substrate 102. The interconnect structure 110 can be used as a redistribution layer (RDL) structure for wiring. The interconnect structure 110 includes a plurality of conductive layers 106 and a conductive pad 112 formed in a plurality of dielectric layers 108. In some embodiments, the conductive pad 112 is exposed at the top surface of the top of the dielectric layer 108 or protrudes therefrom to serve as a bonding pad.

[0082] The dielectric layer 108 may be made of or include one or more polymer materials. The polymer material(s) may include polybenzoxazole (PBO), polyimide (PI), one or more other suitable polymer materials, or a combination thereof. In some embodiments, some or all of the dielectric layers 108 are made of or include dielectric materials other than polymer materials. The dielectric material may include silicon oxide, silicon carbide, silicon nitride, silicon oxynitride, one or more other suitable materials, or a combination thereof.

[0083] The conductive layer 106 and the conductive pad 112 may be made of copper (Cu), copper alloy, aluminum (Al), aluminum alloy, tungsten (W), tungsten alloy, titanium (Ti), titanium alloy, tantalum (Ta), or tantalum alloy. In some embodiments, the conductive layer 106 and the conductive pad 112 are formed by electroplating, chemical plating, printing, chemical vapor deposition (CVD) process, or physical vapor deposition (PVD) process.

[0084] Afterwards, if Figure 1C As shown, according to some embodiments of the present disclosure, a semiconductor die 120 is formed on a first substrate 102. The semiconductor die 120 includes a substrate 121 and an interconnect structure 122 on the substrate 121. The interconnect structure 122 of the semiconductor die 120 includes a plurality of conductive layers 124.

[0085] In some embodiments, the semiconductor die 120 is cut from a wafer and can be a "known-good-die". The semiconductor die 120 can be a system-on-chip (SoC) chip or a memory die. In some other embodiments, the semiconductor die 120 is a system on integrated circuit (SoIC) device, which includes two or more chips with integrated functions. In some embodiments, the memory die includes a static random access memory (SRAM) device, a dynamic random access memory (DRAM) device, a high bandwidth memory (HBM), or another memory die. The number of semiconductor die 120 is not limited to one, and the number can be adjusted according to the actual application.

[0086] In some embodiments, a plurality of conductive pads 126 are formed below the conductive layer 124 of the semiconductor die 120 , and each conductive pad 126 is bonded to each conductive pad 112 through a plurality of conductive connectors 128 .

[0087] The conductive pad 126 is made of a metal material, such as copper (Cu), copper alloy, aluminum (Al), aluminum alloy, tungsten (W), tungsten alloy, titanium (Ti), titanium alloy, tantalum (Ta), or tantalum alloy. In some embodiments, the conductive pad 126 is formed by electroplating, chemical plating, printing, chemical vapor deposition (CVD) process, or physical vapor deposition (PVD) process.

[0088] The conductive connector 128 is made of a material such as tin (Sn), tin-silver (SnAg), tin-lead (SnPb), tin-copper (SnCu), tin-silver-copper (SnAgCu), tin-silver-zinc (SnAgZn), tin-zinc (SnZn), tin-bismuth-indium (SnBiIn), tin-indium (SnIn), tin-gold (SnAu), tin-zinc-indium (SnZnIn), tin-silver-antimony (SnAgSb), or other suitable materials. In some embodiments, the conductive connector 128 is formed by electroplating, chemical plating, printing, chemical vapor deposition (CVD) process, or physical vapor deposition (PVD) process.

[0089] Next, if Figure 1DAs shown, according to some embodiments of the present disclosure, an underfill layer 130 is formed between the semiconductor die 120 and the interconnect structure 110. The underfill layer 130 surrounds and protects the conductive connector 128. In some embodiments, the underfill layer 130 is in direct contact with the conductive connector 128.

[0090] In some embodiments, the underfill layer 130 is made of or includes a polymer material. The underfill layer 130 may include an epoxy-based resin. In some embodiments, the underfill layer 130 includes a filler dispersed in the epoxy-based resin.

[0091] In some embodiments, the formation of the bottom filling layer 130 includes an injecting process, a spin-on process, a dispensing process, a film lamination process, an application process, one or more other applicable processes, or a combination thereof. In some embodiments, a thermal curing process is used during the formation of the bottom filling layer 130.

[0092] Afterwards, a packaging layer 140 is formed on the bottom filling layer 130. An interface exists between the bottom filling layer 130 and the packaging layer 140, and the interface is lower than the top surface of the semiconductor die 120. The packaging layer 140 surrounds and protects the semiconductor die 120. In some embodiments, the packaging layer 140 is in direct contact with a portion of the semiconductor die 120.

[0093] The encapsulation layer 140 is made of a molding compound material. The molding compound material may include a polymer material, such as an epoxy resin with a filler dispersed therein. In some embodiments, a liquid molding compound material is applied over the semiconductor die 120. The liquid molding compound material may flow into the spaces between the semiconductor die 120. Then, a heat treatment is used to cure the liquid molding compound and transform it into the encapsulation layer 140.

[0094] Afterwards, if Figure 1E As shown, according to some embodiments of the present disclosure, a portion of the encapsulation layer 140 is removed. As a result, the top surface of the semiconductor die 120 is exposed. The top surface of the semiconductor die 120 is substantially flush with the top surface of the encapsulation layer 136. Where applicable, the term "substantially" may also refer to 90% or higher, such as 95% or higher, especially 99% or higher, including 100%.

[0095] In some embodiments, a planarization process is used to thin the encapsulation layer 140. The planarization process may include a chemical mechanical polishing (CMP) process, a grinding process, an etching process, another suitable process, or a combination thereof.

[0096] Subsequently, the encapsulation layer 140 is attached to a carrier substrate 142. In some embodiments, the carrier substrate 142 is used as a temporary substrate. The temporary substrate provides mechanical and structural support in subsequent processing operations, such as those operations that will be described in more detail later. The carrier substrate 142 is made of a semiconductor material, a ceramic material, a polymer material, a metal material, another suitable material, or a combination thereof. In some embodiments, the carrier substrate 142 is a glass substrate. In some other embodiments, the carrier substrate 142 is a semiconductor substrate, such as a silicon wafer.

[0097] Afterwards, the first substrate 102 is thinned using the carrier substrate 142 as a support. In some embodiments, the first substrate 102 is thinned from the second surface 102b until the conductive structure 104 is exposed. In some embodiments, the conductive structure 104 is exposed and penetrates the thinned first substrate 102. As a result, a via structure 144 is formed in the first substrate 102. In some embodiments, the via structure 144 is a through substrate via (TSV). In some other embodiments, the via structure 144 may be referred to as a through silicon via.

[0098] Afterwards, if Figure 1F As shown, according to some embodiments of the present disclosure, a passivation layer 150 is formed under the second surface 102b of the first substrate 102, and a conductive pad 152 is formed in the passivation layer 150. A conductive connector 154 is formed under the conductive pad 152. The conductive connector 154 is electrically connected to the via structure 144 through the conductive pad 152.

[0099] The passivation layer 150 is made of poly(p-phenylene-2,6-benzoxazole), PBO, benzocyclobutene (BCB), silicone, acrylate, siloxane, another suitable material, or a combination thereof. In some other embodiments, the passivation layer 150 is made of a non-organic material. The non-organic material includes silicon oxide, undoped silicate glass, silicon oxynitride, silicon nitride, silicon carbide, another suitable material, or a combination thereof. In some embodiments, the passivation layer 150 is formed by a deposition process, such as a physical vapor deposition process (PVD), a chemical vapor deposition (CVD) process, or another applicable process.

[0100] The conductive pad 152 is made of a metal material, such as copper (Cu), copper alloy, aluminum (Al), aluminum alloy, tungsten (W), tungsten alloy, titanium (Ti), titanium alloy, tantalum (Ta), or tantalum alloy. The conductive connector 154 is made of a metal layer, such as copper, copper alloy, nickel, nickel alloy, aluminum, aluminum alloy, tin, tin alloy, lead, lead alloy, silver, silver alloy, or a combination thereof. In some embodiments, the conductive connector 154 is formed by a plating process, such as an electrochemical plating process or a chemical plating process.

[0101] Next, if Figure 1G As shown, according to some embodiments of the present disclosure, the carrier substrate 142 is removed to form the grain structure 10, and the grain structure 10 is formed on the second substrate 160 through the conductive connector 154. The second substrate 160 has a first surface 160a and a second surface 160b. The grain structure 10 is formed on the first surface 160a of the second substrate 160.

[0102] Afterwards, if Figure 1H As shown, according to some embodiments of the present disclosure, the encapsulation layer 164 surrounds and protects the die structure 10, and forms an annular structure 166 above the first surface 160a of the second substrate 160. The annular structure 166 is used to protect the die structure 10 and prevent the die structure 10 from bending.

[0103] The ring structure 166 provides sufficient support function and warpage control. In some embodiments, the ring structure 166 includes a support material, such as a polymer, a metal, a ceramic, or a combination thereof.

[0104] Afterwards, if Fig. 1I As shown, according to some embodiments of the present disclosure, the die structure 10 is turned upside down, a plurality of conductive pads 170 are formed in the second substrate 160, and a plurality of electrical connectors 172 are formed above the conductive pads 170. More specifically, the electrical connectors 172 are formed on the second surface 160b of the second substrate 160.

[0105] Afterwards, if Figure 1J As shown, according to some embodiments of the present disclosure, a first protruding structure 178 is formed in the peripheral area of ​​the second substrate 160. The first protruding structure 178 surrounds the electrical connector 172.

[0106] The first protruding structure 178 is used to provide mechanical and structural support for the second substrate 160. In addition, the first protruding structure 178 is used to control the height of the electrical connector 172.

[0107] The first protruding structure 178 is made of a polymer, a metal, a ceramic, or a combination thereof. In some embodiments, the polymer is poly(methyl methacrylate), PMMA, an epoxy resin having a filler dispersed therein. The filler may include insulating fibers, insulating particles, other suitable elements, or a combination thereof. In some embodiments, the glass transition point (Tg) of the polymer is in the range of about 200 degrees Celsius to about 250 degrees Celsius. In some embodiments, the metal is copper (Cu), a copper alloy, aluminum (Al), an aluminum alloy, tungsten (W), a tungsten alloy, titanium (Ti), a titanium alloy, tantalum (Ta), or a tantalum alloy.

[0108] The first protruding structure 178 is formed by a deposition process and a curing process. In some embodiments, the deposition process includes printing, a chemical vapor deposition (CVD) process, a physical vapor deposition (PVD) process, or another applicable process. In some embodiments, when the first protruding structure 178 is made of a polymer, the curing process is performed at a temperature in the range of about 120 degrees Celsius to about 200 degrees Celsius. In some embodiments, the curing process is performed for a period of time in the range of about 0.5 hours to about 2 hours.

[0109] like Figure 1J As shown, the first protruding structure 178 has a first height H1. Each electrical connector 172 has an original height H1'. In some embodiments, the original height H1' is higher than the first height H1. Since each electrical connector 172 can have a different height, and the engagement surfaces of the electrical connectors 172 can be at the same level. In order to reduce the degree of non-planarity of the engagement surface, the height of the electrical connector 172 is adjusted by the pressurization process 20.

[0110] Next, if Figure 1K As shown, according to some embodiments of the present disclosure, a pressurizing process 20 is performed on the electrical connector 172 and the first protruding structure 178 by the molding device 18 .

[0111] In some embodiments, the press process 20 operates with a force in a range of about 500 Kg to about 5000 kg per grain structure 10. In some embodiments, the press process 20 operates in a temperature range of about 30 degrees Celsius to about 150 degrees Celsius.

[0112] After the pressurization process 20, each of the electrical connector 172 and the first protruding structure 178 is the same height, for example, the first height H1. In some embodiments, the first height H1 is in the range of about 0.2 mm to about 0.8 mm. The electrical connector 172 has a substantially flat top surface. Where applicable, the term "substantially" may also refer to 90% or higher, such as 95% or higher, especially 99% or higher, including 100%.

[0113] Afterwards, if Figure 1L As shown, according to some embodiments of the present disclosure, after the pressurization process 20, the third substrate 180 is provided with a second protrusion structure 182, and the second protrusion structure 182 faces the first protrusion structure 178. Similar to the first protrusion structure 178, the second protrusion structure 182 also serves as a mechanism and structural support.

[0114] The first protruding structure 178 and the second protruding structure 182 are configured to be used as alignment marks. After the second substrate 160 is bonded to the third substrate 180, the first protruding structure 178 does not overlap with the second protruding structure 182. Before the second substrate 160 is bonded to the third substrate 180, the electrical connector 178 below the second surface 160b of the second substrate 160 should be aligned with the corresponding electrical connector 190 formed on the first surface 180a of the third substrate 180. However, in some embodiments, the electrical connector 178 may not be aligned with the corresponding electrical connector 190, and thus reduce the bonding reliability of the second substrate 160 to the third substrate 180.

[0115] In order to prevent the misalignment problem, the first protrusion structure 178 and the second protrusion structure 182 are respectively formed on the second substrate 160 and the third substrate 180. During the bonding of the second substrate 160 to the third substrate 180, the alignment between the electrical connector 178 and the electrical connector 190 is controlled by detecting the positions of the alignment marks (e.g., the first protrusion structure 178 and the second protrusion structure 182). Therefore, the accuracy of the alignment is improved by forming the first protrusion structure 178 and the second protrusion structure 182.

[0116] The second protruding structure 182 is made of polymer, metal, ceramic, or a combination thereof. In some embodiments, the first protruding structure 178 and the second protruding structure 182 are made of different materials. The third substrate 180 is a printed circuit board (PCB), a ceramic substrate, or another suitable packaging substrate. In some embodiments, the first protruding structure 178 and the second protruding structure 182 are both the same height H1.

[0117] Then, if Figure 1MAs shown, according to some embodiments of the present disclosure, the second substrate 160 is bonded to the third substrate 180. More specifically, each electrical connector 178 is connected to each corresponding electrical connector 190 through a reflow process to form an electrical connector 192.

[0118] After bonding the second substrate 160 to the third substrate 180, the first protrusion structure 178 does not overlap the second protrusion structure 182. The first protrusion structure 178 is closer to one of the electrical connectors 172 than the second protrusion structure. In some embodiments, the outer sidewall of the first protrusion structure 178 is substantially aligned with the outer sidewall of the annular structure 166.

[0119] Since the first protruding structure 178 is configured to provide mechanical and structural support for the second substrate 160, the warping of the second substrate 160 can be reduced. In addition, the first protruding structure 178 is configured to control the height of the electrical connector 172 when the pressurization process 20 is performed on the electrical connector 172. By forming the first protruding structure 178 and the second protruding structure 182, when the second substrate 160 is bonded to the third substrate 180, the problem of misalignment is reduced. Therefore, the bonding reliability of the package structure 100a is improved.

[0120] Figure 1M' FIG. 1 is a cross-sectional view of a package structure 100 b according to some embodiments of the present disclosure. In addition to initially forming a third protruding structure 184 above the third structure 180 and next to the second protruding structure 182, the package structure 100 b is similar to the package structure 100 b. Figure 1M The process and materials used to form the package structure 100c may be similar or identical to the process and materials used to form the package structure 100a, and will not be described in detail herein.

[0121] After the second substrate 160 is bonded to the third substrate 180 , the first protruding structure 178 is between the second protruding structure 182 and the third protruding structure 184 .

[0122] The space between the second protruding structure 182 and the third protruding structure 184 is used to set the first protruding structure 178. The first protruding structure 178, the second protruding structure 182 and the third protruding structure 184 are used as alignment marks. There is a first space S1 between the first protruding structure 178 and the second protruding structure 182, and there is a second space S2 between the first protruding structure 178 and the third protruding structure 184. In some embodiments, the first space S1 is substantially equal to the second space S2. If the first space S1 or the second space S2 is not within a specific range, the electrical connector 172 may not be aligned with the corresponding electrical connector 190. Therefore, the bonding strength between the second substrate 160 and the third substrate 180 is reduced due to misalignment.

[0123] In some embodiments, the first space S1 is in a range of about 0.05 mm to about 0.5 mm. In some embodiments, the second space S2 is in a range of about 0.05 mm to about 0.5 mm. When the first space S1 and the second space S2 are in the above ranges, the accuracy of alignment between the second substrate 160 and the third substrate 180 is improved.

[0124] Figure 2A Some embodiments of the present disclosure are shown Figure 1H . When viewed from the top, the ring structure 166 has a rectangular shape and surrounds the grain structure 10.

[0125] Figure 2B Some embodiments of the present disclosure are shown Figure 1K A top view of the first protruding structure 178 in FIG. Figure 1L Shown along Figure 2B 1 is a cross-sectional view of the second substrate 160 taken along line segment AA′.

[0126] When viewed from a top view, the first protruding structure 178 has four sub-portions. When viewed from a top view, each of the four sub-portions has an L-shape. Each sub-portion of the first protruding structure 178 is located at a corner of the first substrate 160. In some embodiments, each sub-portion of the first protruding structure 178 has a first width W1 in a range of about 0.1 mm to about 1 mm. In some embodiments, each sub-portion of the first protruding structure 178 has a first length L1 in a range of about 1 mm to about 5 mm.

[0127] Since the electrical connector 172 is pressurized in the pressurizing process 20 , the electrical connector 172 has a rectangular shape.

[0128] Figure 2C Some embodiments of the present disclosure are shown Figure 1L FIG. 1 is a top view of the second protruding structure 182 in FIG. Figure 1L Shown along Figure 2C BB' is a cross-sectional view of the third substrate 180.

[0129] When viewed from a top view, the second protruding structure 182 has four sub-portions. Each sub-portion of the second protruding structure 182 is located at a corner of the third substrate 180. In some embodiments, each sub-portion of the second protruding structure 182 has a second width W2 in a range of about 0.1 mm to about 1 mm. In some embodiments, each sub-portion of the second protruding structure 182 has a second length L2 in a range of about 1 mm to about 5 mm.

[0130] Figure 2C' A top view of the second protruding structure 182 and the third protruding structure 184 according to some embodiments of the present disclosure is shown.

[0131] Similar to the second protruding structure 182, the third protruding structure 184 also has four sub-portions when viewed from a top view. Each sub-portion of the third protruding structure 184 is located at a corner of the third substrate 180. In some embodiments, each sub-portion of the third protruding structure 184 has a third width W3 in the range of about 0.1 mm to about 1 mm. In some embodiments, each sub-portion of the third protruding structure 184 has a third length L3 in the range of about 1 mm to about 5 mm.

[0132] FIG. 3A to FIG. 3E FIG. 1 shows a cross-sectional view of various stages of forming a package structure 100c according to some embodiments of the present disclosure. In addition to the second substrate 160 being warped or bent upward, the package structure 100c and Figure 1M The process and materials used to form the package structure 100c may be similar or identical to the process and materials used to form the package structure 100a, and will not be described in detail herein.

[0133] like Figure 3A As shown, the second substrate 160 exhibits warpage after the thermal process. Afterwards, a flux 171 is formed over the conductive pad 170. The conductive material 174 is below the device 22 and faces the flux 171. Since the second substrate 160 exhibits warpage, the flux 171 is formed on the non-planar top surface of the second substrate 160.

[0134] The flux 171 is used to inhibit or prevent the formation of oxides on the surface of the electrical connector 172 during the reflow process. Bonding defects caused by oxides during the subsequent reflow process can be prevented. In some embodiments, the flux 171 includes chloride, fluoride, resin, or another suitable material.

[0135] In some embodiments, the warping of the second substrate 160 is caused by a mismatch in the coefficient of thermal expansion (CTE) between two different packaging materials (e.g., the die structure 10 and the second substrate 160) during the packaging process. The packaging process may be a process of mounting the die structure 10 ( Figure 1G ) or forming a packaging layer 164 ( Figure 1H ).

[0136] Next, if Figure 3BAs shown, according to some embodiments of the present disclosure, a conductive material 174 is disposed on the corresponding flux 171 to form a plurality of electrical connectors 172 by a reflow process. As a result, the electrical connectors 172 are formed on the non-planar second surface 160b of the second substrate 160. In some embodiments, the electrical connectors 172 provide a concave engagement surface for bonding to the third substrate 180. In some other embodiments, the electrical connectors 172 provide a convex engagement surface for bonding to the third substrate 180.

[0137] It should be noted that since each electrical connector 172 has the same size and is formed on the non-planar second surface 160b of the second substrate 160, each electrical connector 172 has a different height (level). In some embodiments, the electrical connector 172 located in the central area of ​​the second substrate 160 is lower than the electrical connector 172 located in the peripheral area of ​​the second substrate 160.

[0138] In some embodiments, there is a distance G between the highest point and the lowest point of the electrical connector 172. If the distance G is too large, the non-planarity of the electrical connector 172 may cause failure in subsequent assembly processes.

[0139] Afterwards, in order to provide a flat bonding surface, e.g. Figure 3C As shown, according to some embodiments of the present disclosure, a pressurizing process 20 is performed on the electrical connector 172 and the first protruding structure 178 by the molding device 18 .

[0140] It should be noted that if Figure 3C As shown, the first protrusion structure 178 is formed on the inclined surface of the second substrate 160. The first protrusion structure 178 has a flat top surface and an inclined bottom surface.

[0141] Next, if Figure 3D As shown, according to some embodiments of the present disclosure, the molding device 18 is removed, and the electrical connector 172 provides a flat engagement surface. The degree of non-planarity of the electrical connector 172 is reduced by the pressurization process 20. A portion of the electrical connector 172 is pressurized in the first region 11 (e.g., the peripheral region), and the pressurized electrical connector 172 has a substantially flat top surface. Another portion of the electrical connector 172 is not pressurized in the second region 12 (e.g., the central region), and the unpressurized electrical connector 172 has a curved top surface.

[0142] The first protruding structure 178 has a first height H1. The electrical connector 172 that is pressed in the first region 11 (e.g., the peripheral region) has a second height H2 and a second width D2, and the electrical connector 172 that is not pressed in the second region (e.g., the central region) has a third height H3 and a third width D3. In some embodiments, the first height H1 is less than the second height H2, and the second height H2 is less than the third height H3. In some embodiments, the second width D2 is greater than the third width D3.

[0143] Afterwards, if Figure 3E As shown, according to some embodiments of the present disclosure, the third substrate 180 is provided with the second protrusion structure 182 , and the second substrate 160 is bonded to the third substrate 180 .

[0144] Since the second substrate 160 may exhibit warpage, if the electrical connector 172 is not pressurized in the pressurization process 20, non-planarity of the bonding surface of the electrical connector 172 may occur. As a result, a portion of the electrical connector 172 may not contact the third substrate 180, and the bonding reliability between the second substrate 160 and the third substrate 180 is reduced. In order to compensate for the warpage, the electrical connector 172 is pressurized before the second substrate 160 is bonded to the third substrate 180. Therefore, the co-planarity of the bonding surface of the electrical connector 172 is improved, and the bonding reliability of the package structure 100c is improved.

[0145] Figure 3E' FIG. 1 is a cross-sectional view of a package structure 100d according to some embodiments of the present disclosure. In addition to initially forming a third protruding structure 184 above the third substrate 180 and next to the second protruding structure 182, the package structure 100d is similar to the package structure 100d. Figure 3E The process and materials used to form the package structure 100d may be similar or identical to the process and materials used to form the package structure 100c, and will not be described in detail herein.

[0146] like Figure 3E' As shown, the first protruding structure 178 is between the second protruding structure 182 and the third protruding structure 184. The second protruding structure 182 has a fourth height H4, and the third protruding structure 184 has a fifth height H5. In some embodiments, the fifth height H5 is greater than the first height H1, and the first height H1 is greater than the fourth height H4.

[0147] Figure 4A Some embodiments of the present disclosure are shown Figure 3D A top view of the first protruding structure 178 in FIG.

[0148] When viewed from a top view, the first protruding structure 178 has four sub-portions. When viewed from a top view, each of the four sub-portions has an L-shape. Each sub-portion of the first protruding structure 178 is located at a corner of the first substrate 160. In some embodiments, each sub-portion of the first protruding structure 178 has a first width W1 in a range of about 0.1 mm to about 1 mm. In some embodiments, each sub-portion of the first protruding structure 178 has a first length L1 in a range of about 1 mm to about 5 mm.

[0149] The electrical connector 172 in the first region has a rectangular shape because the electrical connector 172 is pressurized in the pressurization process 20. The electrical connector 172 in the second region has a circular shape because the electrical connector 172 is not pressurized.

[0150] Figure 4B Some embodiments of the present disclosure are shown Figure 3E FIG. 1 is a top view of the second protruding structure 182 in FIG.

[0151] When viewed from a top view, the second protruding structure 182 has four sub-portions. When viewed from a top view, each of the four sub-portions has an L-shape. Each sub-portion of the second protruding structure 182 is located at a corner of the third substrate 180. In some embodiments, each sub-portion of the second protruding structure 182 has a second width W2 in a range of about 0.1 mm to about 1 mm. In some embodiments, each sub-portion of the second protruding structure 182 has a second length L2 in a range of about 1 mm to about 5 mm.

[0152] Figure 4B' A top view of the second protruding structure 182 and the third protruding structure 184 according to some embodiments of the present disclosure is shown.

[0153] Similar to the second protrusion structure 182 , the third protrusion structure 184 also has four sub-portions when viewed from a plan view. Each sub-portion of the third protrusion structure 184 is located at a corner of the third substrate 180 .

[0154] Figure 5 FIG. 1 is a cross-sectional view of a package structure 100e according to some embodiments of the present disclosure. In addition to forming a cover structure 190 on the first surface 160a of the second substrate 160, the package structure 100e is Figure 1M The process and materials used to form the package structure 100e may be similar or identical to the process and materials used to form the package structure 100a, and will not be described in detail herein.

[0155] like Figure 5As shown, the cap structure 190 surrounds the die structure 10. Therefore, heat generated from the semiconductor die 120 can be dissipated to the cap structure 172 and then to the external environment. The first protruding structure 178 is directly below the cap structure 190. The outer sidewall of the cap structure 190 is aligned with the outer sidewall of the first protruding structure 178.

[0156] Figure 6 FIG. 1 is a cross-sectional view of a package structure 100f according to some embodiments of the present disclosure. In addition to forming a cover structure 190 on the first surface 160a of the second substrate 160 and forming a fourth protruding structure 186 between two adjacent electrical connectors 192, the package structure 100f is similar to the package structure 100f. Figure 1M' In some embodiments, the fourth protrusion structure 186 may be initially formed under the second substrate 160 and then bonded to the third substrate 180. In some other embodiments, the fourth protrusion structure 186 may be initially formed on the third substrate 180 and then bonded to the second substrate 160.

[0157] Figure 7 FIG. 1 is a cross-sectional view of a package structure 100g according to some embodiments of the present disclosure. In addition to forming a cover structure 190 on the first surface 160a of the second substrate 160, the package structure 100g is Figure 3E The process and materials used to form the package structure 100g may be similar or identical to the process and materials used to form the package structure 100c, and will not be described in detail herein.

[0158] Figure 8 FIG. 3E ′ shows a cross-sectional view of a package structure 100h according to some embodiments of the present disclosure. The package structure 100h is similar or identical to the package structure 100d shown in FIG. 3E ′, except that a cover structure 190 is formed above the first surface 160a of the second substrate 160 and a fourth protrusion structure 186 is formed between two adjacent electrical connectors 192. The process and materials used to form the package structure 100h may be similar or identical to those used to form the package structure 100d, and will not be described in detail herein.

[0159] In some embodiments, the fourth protrusion structure 186 may be initially formed under the second substrate 160 and then bonded to the third substrate 180. In some other embodiments, the fourth protrusion structure 186 may be initially formed on the third substrate 180 and then bonded to the second substrate 160. In some embodiments, the sixth height H6 of the fourth protrusion structure 186 is greater than the fifth height H5 of the third protrusion structure 184.

[0160] The package structures 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h include a die structure 10 formed above a first surface 160a of a second substrate 160. A first protruding structure 178 is formed below a second surface 160b of the second substrate 160 and is adjacent to an electrical connector 172. A second protruding structure 182 is formed above a third substrate 180. The first protruding structure 178 and the second protruding structure 182 are used as supports and alignment marks. By using the first protruding structure 178 as a support, warpage of the second substrate 160 is reduced. By using the first protruding structure 178 and the second protruding structure 182 as alignment marks, misalignment between the second substrate 160 and the third substrate 180 is reduced. In addition, the non-planarity of the electrical connector 172 is reduced by the press process 20, and the first protruding structure 178 is configured to control the height of the electrical connector 172 when the press process 20 is performed on the electrical connector 172.

[0161] An embodiment and a method for forming a package structure are provided. The package structure includes a grain structure formed above a first surface of a second substrate, and an electrical connector formed below a second surface of the second substrate. A first protruding structure and the electrical connector are formed below the second substrate. A second protruding structure is formed above a third substrate. The first protruding structure and the second protruding structure are used as a support, a height controller, and an alignment mark. Therefore, the bonding reliability and performance of the package structure are improved.

[0162] In some embodiments, a method for forming a package structure is provided. The method includes forming a grain structure above a first surface of a first substrate, and forming a plurality of electrical connectors below a second surface of the first substrate. The method also includes forming a first protrusion structure below the second surface of the first substrate, and the electrical connector is surrounded by the first protrusion structure. The method also includes forming a second protrusion structure above the second substrate, and bonding the first substrate to the second substrate. The electrical connector is surrounded by the second protrusion structure, and the first protrusion structure does not overlap with the second protrusion structure. In some embodiments, the method also includes pressing a portion of the plurality of electrical connectors from the second surface of the first substrate before bonding the first substrate to the second substrate, so that the portion of the electrical connector has a substantially flat bottom surface. In some embodiments, the method also includes forming an annular structure or a cover structure above the first surface of the first substrate, wherein the grain structure is surrounded by the annular structure or the cover structure. In some embodiments, the first protrusion structure is directly below the annular structure or the cover structure. In some embodiments, the first protrusion structure and the second protrusion structure are the same height. In some embodiments, the first protrusion structure and the second protrusion structure are both made of a polymer material or a metal. In some embodiments, when viewed from a top view, the first protrusion structure has an L shape. In some embodiments, when viewed from a top view, the first protruding structure has four sub-portions, and each of the sub-portions is located at a corner of the first substrate. In some embodiments, the grain structure includes a plurality of through silicon vias, an internal connection structure, and a grain. The plurality of through silicon vias are formed in the third substrate, the internal connection structure is formed above the through silicon vias, and the grain is formed above the internal connection structure.

[0163] In some embodiments, a method for forming a package structure is provided. The method includes forming a grain structure above a first surface of a first substrate, and forming a plurality of electrical connectors below a second surface of the first substrate. The method also includes forming a first protruding structure next to the electrical connector, and pressurizing a portion of the plurality of electrical connectors in the first region from the second surface of the first substrate, so that each of the electrical connectors in the first region has a substantially flat bottom surface. The method also includes forming a second protruding structure and a third protruding structure above the second substrate, and the second protruding structure and the third protruding structure are of different heights. The method includes bonding the first substrate to the second substrate, and the first protruding structure is located between the second protruding structure and the third protruding structure. In some embodiments, the grain structure includes a plurality of through silicon vias, an internal wiring structure, and a grain. A plurality of through silicon vias are formed in the third substrate, the internal wiring structure is formed above the through silicon vias, and the grain is formed above the internal wiring structure. In some embodiments, another portion of the plurality of electrical connectors in the second region is not pressurized, and one of the electrical connectors in the first region has a first height, the first height is less than the second height of one of the electrical connectors in the second region. In some embodiments, one of the electrical connectors in the first region has a first width, the first width is greater than the second width of one of the electrical connectors in the second region. In some embodiments, the method further comprises forming an annular structure or a cover structure above the first surface of the first substrate, wherein the encapsulation structure is surrounded by the annular structure or the cover structure, and the first protruding structure is directly below the annular structure or the cover structure. In some embodiments, the outer sidewall of the annular structure or the cover structure is aligned with the outer sidewall of the first protruding structure.

[0164] In some embodiments, a method for forming a package structure is provided. The method includes forming a die structure above a first substrate and forming a plurality of electrical connectors below the first substrate. The method also includes forming a first support structure below the first substrate, and the first support structure has a first height, and the method also includes performing a pressurization process on the electrical connector so that the electrical connector includes a first group of pressurized electrical connectors and a second group of non-pressurized electrical connectors. The method also includes using the electrical connector to bond the first substrate to the second substrate, and one of the first group of pressurized electrical connectors has a second height. One of the second group of non-pressurized electrical connectors has a third height. The first height is less than the second height, and the second height is less than the third height. In some embodiments, the method also includes forming a second protruding structure above the second substrate before bonding the first substrate to the second substrate, wherein the second protruding structure is between the first substrate and the second substrate after bonding the first substrate to the second substrate. In some embodiments, the method also includes forming a third protruding structure above the second substrate before bonding the first substrate to the second substrate, wherein the second protruding structure is between the first protruding structure and the third protruding structure. In some embodiments, one of the first group of pressurized electrical connectors has a second width, one of the second group of non-pressurized electrical connectors has a third width, and the second width is greater than the third width. In some embodiments, the method further includes forming a ring structure or a cap structure over the first surface of the first substrate, wherein the grain structure is surrounded by the ring structure or the cap structure, and the first protruding structure is directly below the ring structure or the cap structure.

[0165] The features of several embodiments are summarized above so that those skilled in the art can better understand various aspects of the present disclosure. It should be understood by those skilled in the art that the present disclosure can be easily used as a basis for designing or modifying other processes and structures to achieve the same purposes and / or achieve the same advantages of the embodiments introduced herein. It should also be understood by those skilled in the art that such equivalent configurations do not depart from the concept and scope of the present disclosure, and that various changes, substitutions and modifications may be made to the present disclosure without departing from the concept and scope of the present disclosure.

Claims

1. A method for forming a packaging structure, comprising: forming a grain structure over a first surface of a first substrate; forming a plurality of electrical connectors below a second surface of the first substrate; forming a first protruding structure below the second surface of the first substrate, wherein the plurality of electrical connectors are surrounded by the first protruding structure; forming a second protruding structure above a second substrate; as well as The first substrate is bonded to the second substrate, wherein the plurality of electrical connectors are surrounded by the second protruding structure, and the first protruding structure does not overlap with the second protruding structure.

2. The method for forming a package structure according to claim 1, further comprising: Before bonding the first substrate to the second substrate, a portion of the plurality of electrical connectors is pressed from the second surface of the first substrate so that the portion of the plurality of electrical connectors has a substantially bottom flat surface.

3. The method for forming a package structure according to claim 1, further comprising: An annular structure or a cover structure is formed above the first surface of the first substrate, wherein the grain structure is surrounded by the annular structure or the cover structure. 4 . The method for forming a package structure as claimed in claim 3 , wherein the first protruding structure is directly below the annular structure or the cover structure. 5 . The method for forming a package structure as claimed in claim 1 , wherein the first protruding structure and the second protruding structure are of the same height. 6 . The method for forming a package structure as claimed in claim 1 , wherein the first protrusion structure and the second protrusion structure are both made of polymer material or metal. 7 . The method for forming a package structure as claimed in claim 1 , wherein the first protrusion structure has an L-shape when viewed from a top plan. 8 . The method for forming a package structure according to claim 1 , wherein the first protruding structure has four sub-portions when viewed from a plan view, and each of the sub-portions is located at a corner of the first substrate.

9. The method for forming a package structure as claimed in claim 1, wherein the die structure comprises: A plurality of through silicon vias are formed in a third substrate; an interconnect structure formed above the plurality of through silicon vias; as well as A die is formed above the interconnect structure.

10. A method for forming a packaging structure, comprising: forming a grain structure over a first surface of a first substrate; forming a plurality of electrical connectors below a second surface of the first substrate; forming a first protruding structure next to the plurality of electrical connectors; Pressing a portion of a plurality of electrical connectors in a first region from the second surface of the first substrate so that each of the plurality of electrical connectors in the first region has a substantially flat bottom surface; forming a second protruding structure and a third protruding structure on a second substrate, wherein the second protruding structure and the third protruding structure are at different heights; as well as The first substrate is bonded to the second substrate, wherein the first protruding structure is located between the second protruding structure and the third protruding structure.

11. The method for forming a package structure as claimed in claim 10, wherein the die structure comprises: A plurality of through silicon vias are formed in a third substrate; an interconnect structure formed above the plurality of through silicon vias; as well as A die is formed above the interconnect structure.

12. A method for forming a packaging structure as described in claim 10, wherein another portion of the multiple electrical connectors in a second area is not pressurized, and one of the multiple electrical connectors in the first area has a first height that is smaller than a second height of one of the multiple electrical connectors in the second area. 13 . The method for forming a package structure as claimed in claim 12 , wherein one of the plurality of electrical connectors in the first region has a first width, and the first width is greater than a second width of one of the plurality of electrical connectors in the second region.

14. The method for forming a package structure according to claim 10, further comprising: An annular structure or a cover structure is formed above the first surface of the first substrate, wherein the packaging structure is surrounded by the annular structure or the cover structure, and the first protruding structure is directly below the annular structure or the cover structure. 15 . The method for forming a package structure as claimed in claim 12 , wherein an outer sidewall of a ring structure or a cover structure is aligned with an outer sidewall of the first protruding structure.

16. A method for forming a package structure, comprising: forming a grain structure on a first substrate; forming a plurality of electrical connectors below the first substrate; Forming a first protruding structure below the first substrate, wherein the first protruding structure has a first height; Performing a pressurization process on the plurality of electrical connectors so that the electrical connectors include a first group of pressurized electrical connectors and a second group of non-pressurized electrical connectors; as well as The first substrate is joined to a second substrate using the plurality of electrical connectors, wherein one of the first group of pressurized electrical connectors has a second height, one of the second group of non-pressurized electrical connectors has a third height, the first height is smaller than the second height, and the second height is smaller than the third height.

17. The method for forming a package structure according to claim 16, further comprising: Before the first substrate is bonded to the second substrate, a second protruding structure is formed above the second substrate, wherein after the first substrate is bonded to the second substrate, the second protruding structure is between the first substrate and the second substrate.

18. The method for forming a package structure according to claim 17, further comprising: Before bonding the first substrate to the second substrate, a third protruding structure is formed on the second substrate, wherein the second protruding structure is between the first protruding structure and the third protruding structure.

19. The method for forming a package structure as claimed in claim 16, wherein one of the first group of pressurized electrical connectors has a second width, one of the second group of non-pressurized electrical connectors has a third width, and the second width is greater than the third width.

20. The method for forming a package structure according to claim 16, further comprising: An annular structure or a cover structure is formed above a first surface of the first substrate, wherein the grain structure is surrounded by the annular structure or the cover structure, and the first protruding structure is directly below the annular structure or the cover structure.

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